湍流燃烧场中高阶统计矩的PDF模拟  

PDF Simulation of High-Order Statistical Moments in Turbulent Reacting Flows

作　　者：朱旻明[1] 赵平辉[1] 黄庆[1,2] 叶桃红[1] 刘明侯[1] 陈义良[1] 

机构地区：[1]中国科学技术大学热科学和能源工程系,合肥230027 [2]中南大学能源科学与工程学院,长沙410083

出　　处：《燃烧科学与技术》2009年第1期45-53,共9页Journal of Combustion Science and Technology

基　　金：国家自然科学基金资助项目(50506028)

摘　　要：在非结构网格中,发展有限体积法和Monte Carlo法相结合的混合算法来模拟湍流燃烧,求解相互耦合并且相容的平均密度、动量、能量方程组和脉动速度-标量-频率的联合概率密度函数方程,采用稳态层流火焰面模型计算半详细的化学反应机理.对轴对称钝体火焰驻定器后的扩散燃烧进行模拟,比较了速度和标量的平均量和二阶矩的计算结果和实验数据,并研究了速度的扭率(三阶矩)、扁平因子(四阶矩)及边缘概率密度函数的分布.计算表明,高阶统计矩包含的统计误差比低阶统计矩的大,扭率和扁平系数的峰值则集中在剪切层处.In this paper a consistent hybrid finite volume/Monte Carlo method is developed and applied to triangular unstructured meshes to solve the joint fluctuating velocity-frequency-composition probability density function equation coupled with Reynolds averaged density, momentum and energy equations. Laminar flamelet model is incorporated to calculate semi-detailed chemical mechanisms. The axisymmetric bluff body stabilized diffusion fame is predicted. The simulation results of the first- and second-order moments of turbulent fields, which include mean velocity and scalar fields, Reynolds stresses and root mean squared mixture fraction, are compared with the experimental data. The profiles of skewness （ the third-order moment） and flatness （the fourth-order moment） as well as the marginal probability density function （PDF） distribution of velocity are studied. It is shown that the statistical error in high-order moments is larger than that in low-order moments, and that the values of skewness and flatness reach their peaks in the shear layer.

关 键 词：概率密度函数方法 混合算法 非结构网格 火焰面模型 钝体驻定火焰 

分 类 号：V231.2[航空宇航科学与技术—航空宇航推进理论与工程] TK121[动力工程及工程热物理—工程热物理]